Sunday, August 25, 2013

The 'phantom ecologist' can do better

A loyal reader found this note posted on one of the information kiosks at the DelCarte property last weekend and shared the photo with me. A series of emails with Michele Grenier, the Franklin Conservation Agent, and Jeff Nutting, the Town Administrator, confirmed the following.

Water Chestnut (Trapa natans)

Water chestnut (Trapa natans) has been observed in DelCarte Pond #4, the pond immediately behind this kiosk. The plant has not previously been observed in Franklin.

This is a highly invasive non-native plant most probably introduced by geese and/or swans. If not controlled the pond is expected to be completely controlled by the plants' floating mats in just a couple of years, reducing sunlight and dissolved oxygen to the extent that fish kills can be expected, severely limiting the potential for fishing and bating at DelCarte.

Currently there are dozens of colonies, composed of a few hundred individuals. This population has grown in just a single season (it was not observed in 2012) giving an idea of how it quickly it multiple geometrically.

It is still feasible to control this plant by manually pulling the plants, although it may take several years to completely eradicate it. The plants have dropped their seeds in July, so no control measures are planned until next spring and summer.

If allowed to grow for another year or two, removing the plants manually will be impractical. There are mechanical and chemical controls that can be applied for established infestations, but are prohibitively expensive. next summer is our best chance to control this plant and maintain the ability to fish and boat at DelCarte.

Information will be posted here next spring regarding an attempt in May/June 2014 to manually pull the plant using canoes and kayaks.